Before experimental drugs can be brought to market, they must undergo many rigorous trials to ensure they deliver their medical
benefits effectively and safely. One method commonly used in this process is to compare the effect of a drug with that of a placebo in double-blind tests. Which of the following correctly describes a double-blind test? a. The researchers apply two-layered blindfolds to the study participants so that they cannot see whether they are receiving the drug or a placebo.
b. Neither the researchers nor the study participants know who is receiving the drug and who is receiving the placebo.
c. The researchers know who is receiving the drug and who is receiving the placebo, but they do not know what the supposed effects of the drug should be.
d. The researchers do not know who receives the drug or the placebo, but the participants know and tell them later.
e. None of the above is correct.
b. Neither the researchers nor the study participants know who is receiving the drug and who is receiving the placebo.
Explanation:
In a double-blind test, there are two groups of participants: (1) people who are receiving the new drug and (2) people who are taking a placebo. Neither people from group (1) nor people from group (2) know what they are taking. Also, researchers recollect data from theses groups without knowing which person belongs to each group to avoid any "favoritism" caused by expected results.
<span>The graph portrays
predation. The relationship shows that an
increase in the population of zebra
results in a subsequent increase in the lion population, and vice versa. This,
therefore, means that the lion population
is dependent on the zebra population due to an interaction (predation). The lion population
will always be lower than that of the zebra because of the inefficiencies of energy transfer up the trophic levels (exhibited by a
typical energy pyramid). </span>
In order to "invest" in later stages to get more energy per glucose molecule. It could also be because that is how it is done, it wouldn't be as efficient unless these stages were performed.
